CSV adapter should read from directory relative to the model file

Details

Description

CSV adapter should read from directory relative to the model file.

The mechanism is as follows. Add a new operand "modelUri", containing the URI of the model file, to each operand passed to a custom schema. If the model's URI is a file (i.e. not "inline:"), also add a new operand "baseDirectory" containing the model's directory, as a File object.

The CSV adapter uses this information to look for a directory relative to baseDirectory if the directory specified is relative.

The additional operands are held in the ModelHandler.ExtraOperand enum.